For a natural monopoly to exist

a. a firm's long run average cost curve must exhibit economies of scale throughout the relevant range of market demand.
b. a firm's long run average cost curve must exhibit diseconomies of scale beyond the economically efficient output level.
c. a firm must continually buy up its rivals.
d. a firm must have a governmentminus−imposed barrier.

The gilbert instrument corporation is considering replacing the wood steamer it currently uses to shape guitar sides. the steamer has 6 years of remaining life. if kept,the steamer will have depreciaiton expenses of $650 for five years and $325 for the sixthyear. its current book value is $3,575, and it can be sold on an internet auction site for$4,150 at this time. if the old steamer is not replaced, it can be sold for $800 at the endof its useful life. gilbert is considering purchasing the side steamer 3000, a higher-end steamer, whichcosts $12,000 and has an estimated useful life of 6 years with an estimated salvage value of$1,500. this steamer falls into the macrs 5-year class, so the applicable depreciationrates are 20.00%, 32.00%, 19.20%, 11.52%, 11.52%, and 5.76%. the new steamer is fasterand allows for an output expansion, so sales would rise by $2,000 per year; the newmachine's much greater efficiency would reduce operating expenses by $1,900 per year.to support the greater sales, the new machine would require that inventories increase by$2,900, but accounts payable would simultaneously increase by $700. gilbert's marginalfederal-plus-state tax rate is 40%, and its wacc is 15%.a. should it replace the old steamer? b. npv of replace = $2,083.51

Amanager of a store that sells and installs spas wants to prepare a forecast for january and june of next year. her forecasts are a combination of trend and seasonality. she uses the following equation to estimate the trend component of monthly demand: ft = 30+5t, where t = 1 in january of this year. seasonal relatives are 0.60 for january and 1.50 for june. what demands should she predict for january and june of next year

Ellen and george work for the same company. ellen, a gen xer, really appreciates the flextime opportunities, while george, a baby boomer, takes advantage of the free computer training offered at the company. these policies are examples of